1. Field of the Invention
The present invention relates to an information processing apparatus, and more particularly to an information processing apparatus having a cover member or a display unit which is movable between an open position and a closed position relative to a main body of the apparatus.
2. Related Background Art
In an information processing apparatus, such as a personal computer or a word processor of a so-called lap-top type, a thin display unit such as a liquid crystal display is attached to a main body of the apparatus such that it is movable between an open position and a closed position. In such an apparatus, the display unit itself serves as a cover member. Alternatively, the display unit may be opened or closed by a cover member.
In such an information processing apparatus having a liquid crystal display unit, where full-day operation is required by a communication function, for example, a back light arranged on the back of the display panel is lit or extinguished in accordance with the open position or the closed position of the display unit, that is, whether the display unit is used or not.
In order to save power for the back light and extend its life, a switch for the back light is arranged on the cover member so that the back light is extinguished when an operator moves the cover member to the closed position and is lit when the operator moves the cover to the open position.
In such an apparatus, a disk drive unit such as a hard disk drive (HDD) or a floppy disk drive (FDD) is usually provided as an external storage device. The disk drive unit needs a so-called warm-up time, that is, a time from the actuation of a disk drive motor which drives a rotary disk medium to a steady rotation speed of the motor to permit the accessing. In order to permit high speed accessing, it is necessary to eliminate the waiting time due to the warm-up time. To this end, in one method for controlling the disk drive motor of the disk drive unit, the motor is continuously driven.
In another method for controlling the drive, the motor is deactuated if accessing is not resumed within a predetermined time period after the previous operation of the disk drive unit, that is, the end of the previous accessing operation.
In prior art information processing apparatus, only the control operation to light or extinguish the back light is carried out in response to the opening or the closing of the display unit. It is convenient for a user if information processing, useful to the operator, is automatically carried out in accordance with the open position or the closed position of the display unit, and this provides a user friendly environment. For example,
(a) when the display unit is opened, it means that the user starts to use the apparatus and hence a schedule is displayed. PA0 (b) When the apparatus has a communication function, a record of communication carried out while the display unit was in the closed position (during non-operation) is displayed when the display unit is opened. PA0 (c) When the display unit is closed, that is, when the operation is terminated and information processing is terminated, the processed data is backed up.
Further, where the disk drive motor is continuously driven, particularly in an apparatus which is required for full-day operation, there is a problem of the durability of the device. In addition, a problem of heat generation by the power supply arises and a cooling fan must be continuously driven. This causes noise, particularly at night, and power consumption increases.
The above problem may be solved by deactivating the motor if the accessing operation is not resumed within the predetermined time, as described above. However, since the disk drive motor is stopped if the accessing to the disk drive unit is not frequently performed, a waiting time, due to the warm-up time, is required when the accessing operation is made after a stop. Thus, a high speed accessing is not attained.
Further, in an information processing apparatus which has a switch for the back light on the cover member, if an operator leaves the inner member in the machine with the closed position, power may be shut off by a power failure or another person who does not know that the operator is still using the apparatus, so that data relating to an interrupted job which has not yet been saved in the memory may be lost.